Floresta e Ambiente 2019; 26(Spec No 1): e20180394 https://doi.org/10.1590/2179-8087.039418 ISSN 2179-8087 (online) Original Article Conservation of Nature Sexual Systems of Plants in a Brazilian Montane Forest Monique Perini1 , Henrique Machado Dias2 , Sustanis Horn Kunz2 1Programa de Pós-graduação em Biologia Vegetal, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais – UFMG, Belo Horizonte/MG, Brasil 2Departamento de Ciências Florestais e da Madeira, Universidade Federal do Espírito Santo – UFES, Jerônimo Monteiro/ES, Brasil ABSTRACT In this study, vegetation reproduction has been investigated in order to understand aspects of speciation, structuring and composition of plant communities. Thus, we sought to characterize the frequency of sexual systems from species recorded in seed rain occurring in a tropical rainforest (Atlantic Forest) in Caparaó National Park, Espírito Santo State, Brazil. We collected the seed rain for twelve months, classified and recorded the species for: sexual system; pollination and dispersion syndrome; and fruit type. Then we measured the correlation between these attributes through correspondence analysis. Regarding sexual systems, 71% were hermaphrodites, 13% dioecious, and 11% monoecious. Hermaphrodites are best associated with pollination, dispersion and fruit types, represented by 65% of data variance. This study may contribute to elaborating management and conservation programs taking into account the interaction of plants with the local fauna. Keywords: seed rain, reproductive ecology, woody layer, Caparaó National Park, Atlantic Forest. Creative Commons License. All the contents of this journal, except where otherwise noted, is licensed under a Creative Commons Attribution License. 2/10 Perini M, Dias HM, Kunz SH Floresta e Ambiente 2019; 26(Spec No 1): e20180394 1. INTRODUCTION Some studies have demonstrated positive associations in tropical forests between sexual systems and ecological Plants’ reproductive biology is studied in order to particularities of individuals such as a habit of woody understand aspects of speciation and structuring of plant growth, pollination by generalist insects and fleshy fruits communities, and consequently to obtain information (Matallana et al., 2005; Queenborough et al., 2009), that supports biodiversity conservation. In this case, contributing in dynamics, richness and distribution the essential aspects of reproductive biology consist of forest species, and optimizing the reproductive of sexual selection, pollen syndrome and resource success of individuals in plant communities (Barrett, allocation under the perspective of species evolution. 2013). Matallana et al. (2005) stated that the quantity For example, there are predictions that herbivory may of hermaphrodite woody species in tropical forests influence the evolution of dioecy Goldberg et al.,( 2017; tends to be larger than unisexual species, being 74% Rivkin et al., 2018). hermaphrodites, 14% dioecious and 12% monoecious; a fact that can be explained due to the greater interaction Clarifying plant-animal and plant-environment between plant-animal and plant-environment. interactions and their morphological characteristics help in understanding the ecology of the interaction Therefore, our objective was to characterize the interactions and variations in the frequency of sexual and the evolution of plants with flowers (Peterson & systems in woody species registered from seed rain Kay, 2015). Detection of plant reproductive patterns along the Santa Marta Valley, Caparaó National Park, also helps in understanding the dynamics of gene Espírito Santo State, Brazil. flow in plant communities, promoting important information about local genetic variability (Barrett, We aim at answering the following questions: 1) What 2013). In addition, knowledge of reproductive patterns is the frequency of different sex systems of woody provides data that may support conservation of biotic species present in seed rain from a Dense Montana agents for reproductive success of plant species, because Ombrophilous Forest?; and 2) Are hermaphrodite 90% of the Angiosperms in the world need pollinating species better associated with ecological attributes agents for their fertilization. Hence the disappearance such as pollination syndromes, dispersal and types of animal-plant interactions can lead to reductions of fruit, as expected for tropical forests? in population size and local extinctions (Thomson & Wilson, 2008; Ollerton et al., 2011). 2. MATERIAL AND METHODS The success of a sexual system in a specific region 2.1. Study area may be related to association and coevolution with pollinating agents, allowing efficient deposition The study was developed in a stretch of Dense and pollen removal, which supports irradiation of Montana Ombrophilous Forest in Caparaó National Angiosperms in evolutionary history (Ollerton et al., Park, municipality of Ibitirama, Espírito Santo State, 2011). Hermaphrodite species tend to invest in southeastern Brazil (Figure 1). The Caparaó National attractive floral resources to pollinator fauna and have Park is a Federal Conservation Unit under full protection effective partnerships with these agents; thus, in the located on the border of Minas Gerais and Espírito Santo evolutionary scale they would enjoy more time for this states, under coordinates 20°19’ to 20°37’ S and 41°43’ investment, with the purpose of avoiding or reducing to 41°53’ W. The climate of the region fits in tropical the development of inbred fruits (Thomson & Wilson, type of altitude/subtropical (Cwb), presenting average 2008; Van der Niet & Johnson, 2012). annual temperature of 16.8 °C and average rainfall of Unisex systems (monoecious and dioecious) 1,284 mm (Alvares et al., 2013). are considered products of cross-selection to avoid The study area is located in a valley between two consequences of endogamy. They are usually related to mountain escarpments, which have a main watercourse. wind pollination or small insects, unlike hermaphrodites Seven permanent plots (sample units) with dimensions that show greater interaction with pollinating insects of 20 × 50 m were demarcated. The plots were distributed (Ellis & Johnson 2010; Rymer et al., 2010). along the valley, parallel to the main watercourse, with Floresta e Ambiente 2019; 26(Spec No 1): e20180394 Sexual Systems of Plants in… 3/10 Figure 1. Study area in Caparaó National Park on the border of Minas Gerais and Espírito Santo states, delimitation of the watershed and plot positions. Plots P01 to P07 were used in this study. altitudinal gradient varying between 1,112 and 1,550 meters. both sexes. Dioecious plants have unisexual flowers, Seven of these plots were used in this study. being only male or only female; therefore, in this case In each plot, Perini (2016) allocated 8 collectors there are male and female individuals (Judd et al., 2009). for studying the seed rain (which subsidized this study Data analysis was based on 80 species. It was not of sexual systems) through the technique of collecting possible to identify all seeds at the species level; however, fruits and seeds with fixed collectors, one of the most some families are generalists and have the same sexual effective methods to collect propagules. The collectors system in common between species. Some cases were were arranged in the area in order to obtain a better considered indeterminate for sexual system presenting representation, with an average of 1 collector of 0.25 m2 pollination or dispersion syndrome. When the species for each 100 m2 sample area (Clark et al., 2001). had more than one type of pollination or dispersion Eight collectors were systematically distributed syndrome, we considered two types of syndromes. in each plot with representation of 50% of the sample In addition to the type of sexual system, species were unit, totaling 56 collectors in the sampled area. also classified according to their pollination syndrome, The collectors have a structure of PVC pipes, 2 mm the fruit type and the dispersion syndromes following nylon mesh screens, with dimensions 0.75m × 0.75 m denominations presented by Judd et al. (2009) as 2 (0.5625 m ). They were placed 0.75 m from the ground zoochoric, anemochoric or autochoric. In zoochoric (Clark et al., 2001). dispersion the propagules are dispersed by generalist animals, in anemochoric according to the constancy 2.2. Characterization of reproductive attributes of winds, and autochoric by the species developing The species registered from the seed rain were classified self-dispersal mechanisms, which can be by gravity by Perini (2016) based on the type of sexual system or even by small fruit explosions (Judd et al., 2009). according to the following categories: hermaphrodite, For each type of dispersing agent there are suitable monoecious and dioecious. Hermaphrodite plants are morphologies that facilitate the transport of diaspores. those with androecium and gynoecium in the same They can be attractive to fauna by their colors, smell flower. Monoecious plants have unisexual flowers of and/or sweetened pulp. The fruit can be classified based 4/10 Perini M, Dias HM, Kunz SH Floresta e Ambiente 2019; 26(Spec No 1): e20180394 on arrangement of its pericarp, which can be fleshy or 2.3. Data analysis dry (Judd et al., 2009). According the authors, fleshy A correlation analysis (CA) was used to measure fruits are those presenting fleshy or succulent pericarp, the correlation between types of sexual systems with or which have seeds embedded